In case you want to provide help in form of a pop-up dialog - based on a certain field - Application Designer offers a technique for implementing a value selection help:
The FIELD control offers the property
popupmethod. With this property, a method of the
adapter class is called whenever the user requests a value help inside the
field - by pressing F4 or F7 in the field or by
double-clicking on the field.
A pop-up dialog opens displaying possible data selections.
The value help pop-up dialogs are just normal pop-up dialogs which just have a dedicated purpose.
This document covers the following topics:
Inherited from the Adapter class, there is a
very simple way to provide a value help pop-up dialog. The method
openIdValueHelp is implemented in a generic way and
can be used as follows:
In your adapter, implement a method
findValidValuesForXxx(). Replace
"Xxx" with the name of the property field.
This method must return an array of
com.softwareag.cis.server.util.ValidValueLine objects.
This array contains pairs of IDs and values which are valid data options for
the Xxx property.
When requesting a value help for the corresponding field, a pop-up
dialog displays the ValidValueLine objects which are
passed back from your method. If the user selects an item in the pop-up dialog,
the value is placed in the setXXX method of the
property.
The following Java source shows an example:
// property >department<
String m_department;
public String getDepartment() { return m_department; }
public void setDepartment(String value) { m_department = value; }
public ValidValueLine[] findValidValuesForDepartment()
{
Vector v = new Vector();
v.addElement(new ValidValueLine("EXEC","Executive Board"));
v.addElement(new ValidValueLine("PRO1","Production Line1"));
v.addElement(new ValidValueLine("PRO2","Production Line2"));
v.addElement(new ValidValueLine("SALE","Sales"));
ValidValueLine[] result = new ValidValueLine[v.size()];
v.copyInto(result);
return result;
}
The XML layout looks as follows:
<rowarea name="Field with Value Help">
<itr>
<label name="Department" width="100">
</label>
<field valueprop="department" width="150" popupmethod="openIdValueHelp">
</field>
</itr>
</rowarea>
The result is a field which automatically opens a pop-up dialog when the user presses F4 or F7, or double-clicks on the field.
An additional feature available: instead of displaying pairs of ID and
name, the dialog can display a list of IDs only. There is a constructor of the
ValidValueLine class with only passing an ID to it:
public ValidValueLine[] findValidValuesForDepartment_02()
{
Vector v = new Vector();
v.addElement(new ValidValueLine("EXEC"));
v.addElement(new ValidValueLine("PRO1"));
v.addElement(new ValidValueLine("PRO2"));
v.addElement(new ValidValueLine("SALE"));
ValidValueLine[] result = new ValidValueLine[v.size()];
v.copyInto(result);
return result;
}
Now the pop-up dialog contains only a column containing the IDs:
See the description of the FIELD control for information on
how to implement a valid value help with the
openIdValueCombo method. This method does not open a
pop-up but it open a combo-like selection.
The interface on the server side is exactly the same as for
openIdValueHelp - just the rendering result is
different:
Further information is provided in the description of the FIELD control.
